A mysterious, bright object has appeared from out of nowhere and is now sitting on the surface of Ligeia Mare, the second largest sea on Saturn's moon Titan.
While scientists try to figure out where the object has come from, they are calling it a "transient feature" for now. Informally, they have dubbed the inexplicable geologic formation a "Magic Island," the kind that just magically pops up from out of thin air of all of a sudden.
The discovery, which was published on the June 22 edition of the Nature Geoscience journal, was made using flipping, an old technique that is used to find asteroids, comets and other space objects. Researchers used images taken by the European Space Agency's Huygens probe launched from the Cassini spacecraft and sent to the California Institute of Technology's Jet Propulsion Laboratory on July 10, 2013 to flip through older images taken of the surface of Ligeia Mare on Titan's northern hemisphere. Before 2013, the region on Ligeia Mare where the "magic island" now appears did not have any features.
The researchers believe that this is the first time humans have seen dynamic geological processes at work on Saturn's largest moon, which is only slightly smaller than Earth. Like our home planet, Titan has huge mountains and "sand" dunes and sweeping oceans and lakes the size of the Great Lakes spanning its surfaces, but instead of hydrogen dioxide, the ocean swirls with liquid methane and ethane fed from river-like channels. The Huygens probe, which is the first spacecraft to make a landing on the Outer Solar System, is situated on a flat, sandy plain strewn with icy pebbles.
"This discovery tells us that the liquids in Titan's northern hemisphere are not simply stagnant and unchanging, but rather that changes do occur," says Jason Hofgartner, a planetary scientist at Cornell University and lead researcher. "We don't know precisely what caused this 'magic island' to appear, but we'd like to study it further."
The main theory is the strange island may have appeared as a result of Titan's changing seasons. Titan takes much longer than Earth to transition into the various seasons. Its northern hemisphere has officially entered the vernal equinox, or spring, in August 2009 and is currently getting ready to move into summer solstice, or summer, by May 2017. Hofgartner and his co-authors believe the "magic island" may have appeared because the moon is transitioning between seasons.
The researchers are looking at four possible sources: winds stirring up the waves, bubbles pushed out by gases on the sea floor, frozen sunken solids that have become buoyant due to warmer temperatures, and silt-like solids suspended on the surface of the sea.
